Compact glow discharge device having improved connection means for supplying electrical energy



v June 20, 195? m m ET ALv 3,324,153

COMPACT GLOW DISCHARGE DEVICE HAVING IMPROVED CONNECTION MEANS FORSUPPLYING ELECTRICAL ENERGY Filed March 30, 1964 5 Sheets-Sheet 1lNvENToRs Wa/fer WBic/(m/re seph .BUECU'O' ATTORNEY w. w. BlCKMiRE-i ETAL 3,327,153 COMPACT GLOW DISCHARGE DEVICE HAVING IMPROVED June 20. 196?CONNECTION MEANS FOR SUPPLYING ELECTRICAL ENERGY Filed March 50, 1964ATTORNEY June 20. 1967 w. w. BECKMERE ET AL 3,327,153

COMPACT GLOW DISCHARGE DEVICE HAVING IMPROVED CONNECTION MEANS FORSUPPLYING ELECTRICAL ENERGY Filed March 50, 1964 3 Sheets-Sheet 3 [/5 II I v 4 I, 57 57 mxmxm a9 9/ 2a 9/ IN ENTOR5 Wa/fer ,E/ckm/re A? BYJoseph .Buaard ATTORN EY United States Patent ration of Delaware FiledMar. 30, 1964, Ser. No. 355,560 8 Claims. (Cl. 313-1095) This inventionrelates to glow discharge devices and more particularly to a segmentedglow discharge readout device for visually displaying symbols includingalphabetical letters, numerals, and letters and numerals.

Known types of glow discharge devices have a he-rmetically sealedtransparent tubular envelope with electrical conductors sealed into oneend thereof and contain a visual display which is disposed either normalor parallel to the longitudinal axis of the envelope. The displayincludes cathode segments which may be shaped in the form of numerals,alphabetical letters, or arrayed as a symbol wherein each segment formsa portion of a numeral, an alphabetical letter, or both. Also, eachcathode segment is connected to a conductor whereby energy. is appliedto and activates the cathode segment.

In addition to the visual display, the envelope contains a gas at glowdischarge pressure and an electrically conductive anode. Thus, byapplying a specific voltage difference to the conductor attached to theanode and one or more of the conductors attached to the segments, thereis provided a means for causing a glow discharge to appear immediatelyadjacent the activated segment or segments whereby a visual displayviewable through the envelope is provided.

While such devices have provided a great impetus to the adoption ofreadout devices, it has been found that numerous conditions exist whichtend to deter the use of such devices in some applications. For example,the ratio of space used to space available within a tubular envelope inthe known display devices leaves much to be desired. Also, tubularconfigurations are not particularly well suited for a panel-typedisplay. Moreover, the known connecting means for applying externalenergy to the display are not particularly adapted to the printedcircuit art and panel-type displays wherein such devices are frequentlyused.

Therefore, it is an object of this invention to provide an improved glowdischarge visual display device.

Another object of the invention is to enhance the ratio of used toavailable space within a glow discharge visual display device.

Still another object of the invention is to improve the means forenergizing the visual display of a glow discharge device.

A further object of the invention is to provide a glow discharge devicehaving an enhanced resistance to vibration and shock.

These and other objects are achieved in one aspect of the invention by avacuum-tight envelope which includes a transparent portion and ishermetically sealed to a rigid planar vacuum-tight insulating support toprovide an enclosure containing a gas at glow discharge pressure, atleast one visual display of cathode segments wherein each segment isinsulated from the other and all are attached to the surface of thesupport facing the envelope transparent portion, and 'a transparentanode having an electrically conductive surface and disposedintermediate the cathode segments and the envelope transparent portion.Each of the cathode segments and the anode have an electrical connectionto an electrical conductor external to the envelope and attached to thesupport.

For a better understanding of the present invention, together with otherand further objects, advantages, and capabilities thereof, reference ismade to the following disclosure and appended claims in connection withthe accompanying drawings in which:

FIG. 1 is a plan view in section of one embodlment of the invention;

FIG. 2 is a plan view in section of another embodiment of the invention;

FIG. 3 is a plan view from the bottom, showing the electricalconnections of the embodiment of FIG. 1;

FIG. 4 is a cross-sectional view taken along line 4-4 of FIG. 3illustrating the interconnection between the segments of FIG. 1 and theelectrical connections of FIG. 3;

FIG. 5 is a cross-sectional view of still another embodiment of theinvention;

FIG. 6 is a cross-sectional view directed to the placement of an anodewithin the envelope; and

FIG. 7 is another cross-sectional view directed to an alternate anodeplacement in the embodiment of FIG. 2.

Referring to the drawings, FIG. 1 illustrates one embodiment of a glowdischarge device 9 having a transparent envelope 11, an anode 13, acathode segment display 15, an insulator support 17, and a plurality ofspaced contact fingers 19.

The envelope 11 is a substantially rectangular boxlike configuration ofa transparent and vacuum-tight material such as ordinary lead or limeglass and is hermetically sealed to the support 17 at a jointure 21 byany one of numerous well-known methods of making such seals. Also, theenvelope 11 includes an exhaust and sealing means 23 which permits thereplacement of the atmosphere within the hermetically sealed envelope 11and support 17 with a gas at glow dischange pressure.

Adhered to the inner surface of the envelope 11 is a transparent anode13 of an electrically conductive material such as, for example, a layerof stannous oxide. This anode 13 is disposed in a plane substantiallyparallel to the cathode segments of the display 15 and spacedsubstantially equi-distant from each of the segments. A contacting meansQ is provided intermediate the anode 13 and the support 17 whichelectrically connects the anode to an electrical conductor disposed onthe surface of the support 17 opposite to the surface thereof whereon isdisposed the display 15, as will be explained hereinafter.

Bonded to the support 17 and disposed intermediate thereto and facingthe transparent anode 13 and envelope 11 is a cathode segment display15. This display 15 includes a plurality of cathode segments designatedby the letters A, B, C, D, E, F, G, H, I, J, K, L, M, N, and P and isarrayed in a substantially rectangular configuration in a planesubstantially parallel to the anode 13 and the support 17. Also therectangular configuration has therein pairs of segments substantiallynormal to the opposing sides and diagonal to the corners thereof and mayinclude as few as 12 cathode segments, depending upon the visualqualities desired. Moreover, the segments A through N and P of thedisplay 15 are arrayed such that numerals 0 through 9 and all of theletters of the alphabet, along with a decimal point, are provided in aneconomical and restricted area. Thus, the display provides a symbolwhich may be in the form of a numeral,

an alphabetical letter, or both.

The segments A through N and P of the display 15 are of a nickelmaterial, although steel, iron, molybdenum, and tungsten are equallyapplicable and appropriate and are insulatingly spaced from one anotherto provide individual electrical identities. Also, the segments Athrough N and P are bonded to the surface of the support 17 by any oneof numerous well-known processes. For instance, the surface of thesupport 17 may be metallized and the undesired metal portions removed byetching or sand-blasting, or the segments may be prefabricated and gluedor adhered to the support. Obviously, numerous well-known and often usedtechniques for forming and attaching the segments to the support areequally applicable and appropriate. Regardless of the technique used,the segments A through N and P are attached to the support 17 to providea substantially planar display 15 facing the anode 13.

The support 17 is a rigid planar insulator having a substantiallyrectangular configuration which extends longitudinally beyond theconfines of the hermetically sealed envelope 11. Preferably, the support17 is of a material such as Photoceram produced by Corning Glass Works,of Corning, N.Y.-, which has a good electrical andmechanical propertiesand may be converted from a transparent to an opaque condition duringthe processing thereof. However, any one of a number of ceramicmaterials are equally applicable so long as they are rigid, hermeticallyseala-ble to the envelope, and are/ or can be made to be vacuum tight,

At one end of the support 17 and extending inwardly therefrom is aplurality of spaced contact fingers 19.

These fingers 19 are disposed on opposite surfaces of the support 17external to the envelope 11 and provide a convenient and commonly usedmeans for applying energy from an external source to the segments Athrough N and P and to the anode 13 within the envelope 11. Essentially,the contact fingers 19 are adapted for use with the ordinary printedcircuit type of contact.

In order to provide an electrical connection between the fingers 19 andthe segments A through N and P, as well as the contacting means Q of theanode 13, a plurality of conductors 25 are bonded to the oppositesurface of the support 17 as illustrated in FIG. 3. Herein, theconductors 25 are designated by the same alphabetical letters as thesegments A through N and P and the anode Q of FIG. 1 and are directlyconnected thereto as illustrated in the cross-sectional view of FIG. 4taken along the line 44 of FIG. 3.

As can be readily understood, the cathode segment display 15, as well asthe conductors 25 and the contact fingers 19, are preferably of the sameconductive material and bonded to the support 17 in a similar manner.Moreover, the process for providingand bonding the display 15,conductors 25, and contact fingers 19 is carried out in substantiallythe same manner and essentially in the same sequence in the interest ofminimum cost per unit.

Referring to FIG. 4, the support 17 has an aperture 27 therethroughwhich is filled with the same electrical COIl". ducting material as isprovided for the cathode segment display 15 and the conductors 25.Additionally, the aperture 27 is hermetically sealed with a glob 28 ofglass frit of which any number are available and commonly used in thesealing art. Thus, each cathode segment A through N and P of the thedisplay 15, as well as the anode conecting means Q, is electricallyconnected to one of the conductors 25 which is directly connected to acontact finger 19 adapted for external application of energy thereto.

In an alternate embodiment as illustrated in FIG. 5, a discharge device29 includes a substantially semicylindrical transparent glass enevelope31 having an electrically conductive transparent anode 33 bonded to theinner surface thereof and facing a planar cathode segment display 35attached to a rigid planar insulator support 37.

The envelope 31 is hermetically sealed to the support 37 at a jointure39 and includes therein a gas at glow discharge pressure and the anode33 and display 35 which are electrically connected through the support37 to a plurality of electrical conductors 41. Thus, a wider angle forviewing the display is provided without a sacrifice in the ratio of usedspace to available space within the envelope 31,

In another embodiment, FIG. 6 illustrates a glow discharge device 43having a transparent glass envelope 45 hermetically sealed to a rigidplanar insulator support 47 whereon is atached a cathode segment display49. However, in this embodiment the anode 51 is an electricallyconductive transparent layer, such as stannous oxide, adhered to atransparent substrate 53 which is spaced from the envelope 45 and thedisplay 49 by a pair of support members 55 and 57 attached to thesupport 47.

Also, each member of the cathode segment display 49,.

as Well as the anode 51, is directly connected electrically to aconnecting pin 59 aflixed t0 the support 47. The connecting pin 59 isslid through an aperture 61 in the support 47 and brought into contactwith a member of the display 49 at a jointure 63, Moreover, the pin 59has a platform 65 which limits the advance thereof through the support47 and which serves to hermetically seal the aperture 61 and hold thepin upon application of a glob 28 of glass frit to the platform 65 andthe support 47 immediately adjacent thereto.

Alternately, FIG. 2 illustrates a glow discharge device 6 7 whichincludes a transparent box-like glass envelope 69 hermetically sealed toa substantially rectangular planar insulator support 71 at a jointure 73and including therebetween a gas at glow discharge pressure, atransparent electrically conductive anode 75 adhered to the envelope 69,and a cathode segment display 77 attached to the support 71 and in aplane substantially parallel to and facing the anode 75 and the envelope69.

The display 77 includes a plurality of individualsegments A" through N"and P electrically isolated from each other and arrayed in asubstantially rectangular configuration as previously described inFIG. 1. Each segment A through N and P is essentially a rectangularstrip of nickel, iron, tungsten, or similar applicable metals and isaffixed to the support 71 and electrically connected therethrough to aconnecting pin 79.

Additionally, FIG. 7 illustratesv still another embodiment of a glowdischarge device 81 wherein a transparent box-like glass envelope 83 ishermetically sealed to a rigid planar insulator support 85 and includestherebetween a gas at glow discharge pressure, an electricallyconductive and transparent anode 87, such as a wire mesh, spaced fromthe envelope 83 and surrounding a cathode segment display 89. Moreover,each member of the display 89, as well as the anode 87, is afiixed tothe support 85 and electrically connected through the support 85 to anexternal connecting pin 91.

In a specific structure, a photoceram support having a length of about2.25 inches, a width of 1.25 inches, and a thickness of 0.06 inch wasnickel plated and a portion of the nickel removed to provide .a displaysubstantially as illustrated in FIG. 1. The display had a width of about1 inch and a length of approximately 1.5 inches, while each cathodesegment had a thickness of about 0.005 inch and a width of about 0.06inch. The display was hermetically sealed within a box-like glassenvelope having a layer of stannous oxide on the inner surface thereofand the atmosphere therein replaced with a neon-argon gas mixture at apressure of approximately 12 mm. of mercury.

After the usual processing and stabilization period, a voltagedifference of about V. DC. was applied between the anode and the cathodesegments with the anode positive with respect to the cathode. Thereupon,the resultant glow discharge was rated at approximately 200foot-lamberts and clearly readable even under adverse ambient lightingconditions.

Thus, there has been provided a glow discharge device having a uniqueand unexpected resistance to shock and vibration. The device isespecially applicable to panel-type displays as well as the frequentlyencountered block-type printed circuit electrical connecting means.Moreover, the ratio of used to available space within the envelope farsurpasses any of the known types of glow discharge devices while thereadability and appearance of the paneltype display, as well as thecompactness thereof, is enhanced by the device.

While there have been shown and described what are at present consideredthe preferred embodiments of the invention, it will be obvious to thoseskilled in the art that various changes and modifications may be madetherein without departing from the invention as defined by the appendedclaims.

What is claimed is:

1. A glow discharge device comprising:

a rigid vacuum-tight planar insulating support having a plurality ofcathode segments attached to one surface thereof and arranged to providea display symbol, each one of said segments being electrically connectedthrough the support to a conductor attached to the opposite surfacethereof;

an envelope enclosing said segments and hermetically sealed to saidsupport, said envelope having a transparent portion facing said segmentsand containing a gas at glow discharge pressure; and

a transparent electrically conductive anode disposed intermediate theenvelope transparent portion and said segments and spaced substantiallyequidistantly from each of said segments, said anode being elec tricallyconnected to a conductor bonded to said support and external to saidenvelope.

2. A glow discharge device comprising:

a vacuum-tight planar ceramic support having a plurality of cathodesegments bonded to one surface thereof and arranged to provide at leastone visual display symbol, said segments being electrically insulatedfrom each other and each segment electrically connected through thesupport to an electrical conductor attached to the opposite surfacethereof; and

a transparent glass envelope enclosing said segments and hermeticallysealed to said support, said envelope containing a gas at glow dischargepressure, and a transparent electrically conductive anode disposedwithin and intermediate said envelope and said segments and spacedsubstantially equidistantly from each of said segments, said anodehaving an electrical connection to a conductor external to saidenvelope.

3. A glow discharge device comprising:

a vacuum-tight planar ceramic support having a plurality of cathodesegments insulated from each other and bonded to one surface of thesupport, said segments being arrayed in a substantially rectangularconfiguration having segment pairs extending in a directionsubstantially normal to the sides and intermediate diagonal corners ofthe configuration with each segment electrically connected through thesupport to an electrical conductor attached to the support surfaceopposite the bonded cathode segment surface;

a transparent glass envelope enclosing said segments and hermeticallysealed to said support, said envelope containing a gas at glow dischargepressure; and

a transparent anode having at least an electrically conductive surfaceand disposed intermediate said envelope and said segments and spacedsubstantially equidistantly from each of said cathode segments, saidanode having an electrical connection to an electrical conductorexternal to said envelope.

4. A glow discharge device comprising:

a substantially box-shaped transparent glass envelope hermeticallysealed to a substantially rectangular vacuum-tight planar ceramicsupport and containing therebetween a gas at glow discharge pressure, aplurality of cathode segments attached to the surface of said supportwithin said envelope and arrayed as a visual display facing saidenvelope, and a transparent anode having at least an electricalconductive surface and disposed intermediate said envelope and saidsegments and spaced substantially equidistantly from each of saidcathode segments, each of said cathode segments and said anode beingelectrically connected to an electrical conductor bonded to the supportsurface external to the envelope and opposite to the attached cathodesegment surface with each of said conductors directly connected to oneof a plurality of electrical conducting fingers bonded to oppositesurfaces at one end of said support and extending inwardly therefrom.

5. A glow discharge device comprising:

a rigid planar vacuum-tight insulating support having a plurality ofcathode segments insulated from one another and attached to saidsupport, said segments being arrayed in a plane substantially parallelto said support to provide at least one visual display symbol with eachone of said segments having an electrical connection through saidsupport to a conductor attached to the opposite surface thereof;

an envelope hermetically sealed to said support and enclosing saidsegments therebetween, said envelope having a transparent portion in aplane substantially parallel to said display and containing a gas atglow discharge pressure; and

a transparent electrically conductive anode bonded to the transparentportion of said envelope and disposed intermediate said envelope andsaid display, said anode having an electrical connection to a conductorattached to said support external to said envelope.

6. A glow discharge device comprising:

a semi-cylindrical transparent glass envelope hermetically sealed to asubstantially rectangular vacuum-tight planar insulator support andcontaining a gas at glow discharge pressure, a plurality of cathodesegments insulated from one another and attached to the surface of andin a plane substantially parallel to said support, and a wire meshelectrically conductive anode substantially parallel to said segmentsand intermediate said segments and said envelope with each of saidsegments and said anode having an electrical connection through thesupport to an external conductor attached thereto.

7. The glow discharge device of claim 5 wherein said support and saidenvelope are substantially rectangular in shape with said envelopehaving a substantially rectangular-shaped peripheral surfacehermetically sealed to said support.

8. The glow discharge device of claim 5 wherein said support andenvelope are substantially rectangular-shaped and said segmentsproviding said visual display symbol are arrayed in a substantiallyrectangular configuration with segment pairs extending in a directionsubstantially normal to the sides and intermediate diagonal corners ofthe configuration.

References Cited UNITED STATES PATENTS 2,783,408 2/1957 Williams et a1.313-l09.5 3,067,354 12/1962 Peterson 313109.5 X 3,187,320 6/1965 Kupsky313-1095 3,260,881 7/1966 Kuchinsky 313-1095 FOREIGN PATENTS 908,697 10/1962 Great Britain.

JAMES W. LAWRENCE, Primary Examiner. S. A. SCHNEEBERGER, AssistantExaminer.

1. A GLOW DISCHARGE DEVICE COMPRISING: A RIGID VACUUM-TIGHT PLANARINSULATING SUPPORT HAVING A PLURALITY OF CAHODE SEGMENTS ATTACHED TO ONESURFACE THEREOF AND ARRANGED TO PROVIDE A DISPLAY SYMBOL, EACH ONE OFSAID SEGMENTS BEING ELECTRICALLY CONNECTED THROUGH THE SUPPORT TO ACONDUCTOR ATTACHED TO THE OPPOSITE SURFACE THEREOF; AN ENVELOPEENCLOSING SAID SEGMENTS AND HERMETICALLY SEALED TO SAID SUPPORT, SAIDENVELOPE HAVING A TRANSPARENT PORTION FACING SAID SEGMENTS ANDCONTAINING A GAS AT GLOW DISCHARGE PRESSURE; AND A TRANSPARENTELECTRICALLY CONDUCTIVE ANODE DISPOSED INTERMEDIATE THE ENVELOPETRANSPARENT PORTION AND SAID SEGMENTS AND SPACED SUBSTANTIALLYEQUIDISTANTLY FROM EACH OF SAID SEGMENTS, SAID ANODE BEING ELECTRICALLYCONNECTED TO A CONDUCTOR BONDED TO SAID SUPPORT AND EXTERNAL TO SAIDENVELOPE.